The question which has been raised is "How does one draft a patent specification in a form to meet the requirement of all the countries?"

I am a qualified English lawyer, a solicitor, and my practice is focused on post-grant matters, validity, infringement, litigation and post-grant amendment. While I have been involved in discussions on amendments to patent specifications pre-grant, that has only happened on one or two occasions in my career and I cannot describe myself as an expert on it. I therefore propose to consider the problems that can potentially arise to an English specification (whether granted through the EPO or through the UK Patent Office) when it gets to court. (I also have one suggestion on drafting claims.) I shall also touch very briefly on the position as I understand it in the Netherlands and Germany. No doubt I shall throw myself open to comments from the floor from my Dutch and German colleagues and I shall be very happy to have any misconceptions that I have corrected for the benefit of you all.

The English court's approach

As you know the patent judges in the English courts are former barristers with technical skills and many years of practice at the Patent Bar; and that is true in the High Court and the Court of Appeal. In the House of Lords we have Lord Hoffmann who has sat as one of the patent judges and is very knowledgeable and understanding about technology. The English Courts have always tried to adopt a very pragmatic approach to specifications and their approach can be broadly summed up by the comments made by Mr Justice Jacob in Raychem Corporation's patent in which he said, in summary:-

• In all cases, and no matter what the nature of the attack on validity or arguments on infringement, the court must identify the inventive concept embodied in the claims. A properly drafted claim would state that concisely. The court was not required to substitute its own language for that of the patentee if the later was clear. But where the claims were prolix and obscure the court should break free of the language and concern itself with what they really meant.
• Within wide limits a patentee could use what language he liked to define his invention. But it was the substance of the patentee's alleged technical contribution, rather than the form and language of the claims, that must impress the court.
• Selection of a group of compositions by reference to an essentially arbitrary parameter having little technical significance did not involve any inventive step. Although it might not be obvious, in the common use of that term, to limit a claim by reference to some particular meaningless and arbitrary parameter, that had nothing to do with patentability. The selection of a group of compositions by reference to such a parameter does not involve any inventive step. Parents were not given for skill in inventing technical meaningless parameters.
• If the patent claim consists of no more than a product or process selected by reference to a set of obviously desirable parameters, then the technical contribution was the selection of those parameters. Since the selection was obvious, so was the claim.

This approach has been confirmed by the Court of Appeal in Hoechst Celanese Corporation v BP Chemicals Limited (The Times, 27th July 1998) where the court was asked how it should approach the meaning of technical words in a patent specification. The court concluded that:-

• It would be wrong to start the task of construction with any preconceived idea.
• Having obtained the knowledge of the notional skilled man, the specification has to be read as a whole to ascertain its meaning and from that the court has to decide the ambit of the monopoly claimed using the guidance in the Protocol on the Interpretation of Article 69 of the Convention on the Grant of European Patents.
• The correct approach was a purposive construction, namely ascertainment of the meaning having regard to the purpose of the word.

The court then rejected a close textual analysis of the words in the specification as being the "literal analysis" that had been rejected by Lord Diplock in Catnic Components v Hill Smith Limited ([1982] RPC 237), the leading case in the UK on the construction of patent specifications and their claims.

However, while saying that the English courts are pragmatic in their approach to the interpretation of UK patent specifications and their claims it is worth remembering that national courts will have to apply their own rules to any alleged infringement because, under the European Patent Convention (EPC) the court must interpret the patents according to their own views so that the position may vary from country to country.

The requirements of an UK patent specification

What are the requirements for an UK patent specification? Under Section 14 of the Patents Act 1977:-

• The specification of an application shall disclose the invention in a manner which is clear enough and complete enough for the invention to be performed by a person skilled in the art (3); and
• The claim or claims shall:-
• (a) define the matter for which the applicant seeks protection;
• (b) be clear and concise;
• (c) be supported by the description; and
• (d) relate to one invention or to a group of inventions which are so linked as to form a single inventive concept (5);
  
  
following Articles 83 and 84 of the EPC.

The sufficiency of the description has to be at the date when the specification is filed, a point established by the House of Lords in Biogen v Medeva ([1997] RPC 1) in 1996. It follows from the decision that if a priority document is relied on the priority document itself must also be sufficient. In order to be sufficient, as appears from sub-section (3) the specification must allow a person skilled in the art to perform the invention, a so called "enabling disclosure" as referred to in Asahi's Application ([1991] RPC 485 (CA)). Note two things. Some correction may be possible to obvious mistakes. For example in Helitune v Stewart Hughes ([1991] FSR 171) the addressee of the specification would have appreciated that the specification contained an error; the court decided that he would notionally and automatically have corrected the error; and this would have rendered the specification sufficient. Accordingly the specification was held sufficient.

Secondly it is important to note that there is no requirement for a "best mode" disclosure. However "best mode" remains an important requirement for the United States so that the best mode needs to be included in any specification which is to be used as the basis for an application there, and any other country where the "best mode" is required.

Note also that, as I understand the position, the US requirement of "best mode" is at the date of actual application, not the priority date. Contrast this with the UK position where, if priority is to be claimed, the application must be sufficient at the date of priority.

Thirdly, although it is not a point of great importance in relation to the UK, the form of the claim is immaterial. The old British style "one part" claim is allowed in the UK Patent Office. Alternatively the conventional European two part claim may be used. Reference numbers, as in the EPO style claims, are allowed. However the Comptroller has allowed a patentee to delete the reference numbers, to add an omnibus claim and to delete the French and German translations of the claim from the UK granted specification of an European patent. (Philips Electronics Patent. ([1987] RPC 244)).

A further point - the UK courts do not normally concern themselves very much with formal questions as to the name of the inventor or the name of the proprietor and, assuming there is no dispute raised by anyone the court will normally accept the position. If there is a dispute, save in cases where the patent has been obtained, ie stolen, the court is normally very pragmatic about allowing corrections to be made at any time.

Claim interpretation and infringement

As you all know, interpretation of claims under European, and therefore UK patents, is on the basis of Article 69 of the European Patent Convention and the Protocol. The idea of "equivalents" as such is dead in the UK. The rule of "purposive construction" must be adopted which I have referred to briefly above in relation to interpretation of technical terms in patent specifications above.

In summary the current view in England is that in considering whether or not an alleged infringement falls within the claims of a patent the court must answer the following questions laid down in the Improver case (Improver Corp v Remington [1990] FSR 181):-

• Does the variant have a material effect upon the way the invention works? If yes, the variant is outside the claim. If no -
• Would this (ie that the variant had no material effect) have been obvious at the date of publication of the patent to a reader skilled in the art? If no, the variant is outside the claim. If yes -
• Would the reader skilled in the art nevertheless have understood from the language of the claim that the patentee intended that strict compliance with the primary meaning was an essential requirement of the invention? If yes, the variant is outside the claim.

(In passing, I find even "purposive construction" difficult to square with the requirement in the Protocol that there should be "a reasonable degree of certainty for third parties". How is there to be any certainty for third parties if the courts can widen the claims in what must, in fact, be an arbitrary fashion, dependant on the court's view of the situation and the merits of the invention in the context of the art at the time of trial. See for example the Court of Appeal's decision about rotary and reciprocating knives in Kastner v Rizla ([1995] RPC 585).

The current position in England seems to be a willingness to read claims more widely, and doubtless at some stage someone will call a halt and we shall start the cycle again.

Procedure for international applications

As I have said, I am not a practising patent attorney so that my experience of patent application and prosecution is, in effect, non-existent. However I will pass on to you one tip which I had recently had from a practising patent attorney.

His company was having great difficulty with translations into Japanese, for linguistic reasons which I will not bother you with. The solution was simple. Their attorneys are all instructed to draft patent claims in the old English-style single part form, and not in the two part European form. This is appropriate for the US; makes the translation easier for the Japanese and is appropriate there; and can be relatively easily amended by European attorneys used to European practice to comply with the two part claims required in the EPO. (He did not say anything about attempting to try to persuade the EPO to adopt single part claims, so I assume that he has not thought that worthwhile!)

The result is that the length of the claim initially is halved, the cost of translation into Japanese is halved, as is the cost of translation into any other country where "English-style" claims are allowed. The US claims are simple to draft. The conversion into European claims is, as I have said, relatively straightforward so that it has apparently led to considerable savings and, perhaps most important of all in relation to Japan, where protection was (and frequently will be) regarded as very important, to reliable claims there.

Amendment

I thought it would be useful if I talked very briefly about the opportunities for amendment of UK patents. Under Section 72(1) of the Act a UK patent can be revoked:-

• (c) if it does not disclose the invention sufficiently clearly (ie does not comply with Section 14(3) of the Act (Article 83 EPC));
  
• (d) if the matter disclosed in the specification extends beyond that disclosed in the application for the patent as filed [or the priority application as filed];
  
• (e) if the protection conferred by the patent has been extended by an amendment which should not have been allowed.
  

It is important to note that a pre-grant amendment may widen the scope of protection given by a claim provided that there is no added matter under Section 76 of the Act. (A.C. Edwards v Acme Signs ([1990] RPC 62 and [1992] RPC 131 (CA) and Southco v Dzus ([1990] RPC 587 and [1992] RPC 299 (CA)). However under (e) a post-grant amendment may not extend the protection given by the patent.

However even if a patent is invalid under (d) or (e) a patentee may still be able to amend, even though it will have been the patentees conduct that caused the prohibited amendment. The court appears to accept that amendment should be allowed apparently on the basis that the amendment sought by the patentee will have been approved by Comptroller or the court (Harding's Patent [1988] RPC 515).

However it is important to remember that the right to amend a patent is in at the discretion of the court or the Comptroller.

The power to amend is granted by Section 75 of the Act under which the Court "may, subject to Section 76 below, [which deals with the question of added matter and claim widening after grant] allow the proprietor to amend the specification of the patent ... as the court ... thinks fit". (75(1)).

This right to amend is discretionary. (The words "may allow".) The court will always take account of the public interest and not allow the patentee and an opponent to "carve up" the amendment.

As part of that, the court will be reluctant to allow amendment if there is substantial delay in seeking amendment and may refuse to allow amendment if it considers that the delay has been unreasonable.

However it normally draws a distinction between an amendment designed to validate and invalidate a claim and an amendment designed to allow enforcement of a valid claim. So that, if claim 1 is invalid and claim 2 is valid, the court will normally allow claim 1 to be deleted and the consequential amendment of claim 2 (possibly a mere re-numbering of claim 2 as claim 1, or the incorporation of the texts of claim 1 into claim 2) to allow the old claim 2 to be enforced.

One other point to remember in UK proceedings is that the applicant for amendment will normally be expected to make very full discovery of all relevant documents and it is incumbent on the proprietor to make full disclosure of the background to the drafting of the invalid claim. It is likely that a proprietor will have to waive any professional privilege that he may otherwise have claimed if he is to be allowed his amendment.

When considering questions of amendment the Comptroller for many years refused to take account of EPO decisions but this seems to have been changed following the decision of the Patents Court in B & B Relay's Application ([1985] RPC 1) in which the Patents Court indicated that an attempt should be made to give the same meaning to any provision of the Act as that given by the relevant EPC provisions. This comment has been reinforced by the comments of the Patents Court in Bristol Myers Squibb Co v Baker Norton Pharmaceuticals ([1998] All ER (d) 415) in which the Patents Court said that "in future, save in the rare event of a specific contention that a provision of the 1977 Act has a different meaning from a corresponding provision of a convention it will be better for all concerned with patent matters in the United Kingdom (and hopefully throughout Europe) to work on the basis that the corresponding provisions of the conventions are of direct effect".

Test of added matter

In Bonzel v Intervention (No. 3) ([1993] RPC 553) the test for examining whether amendment had involved added subject matter was stated to be:-

(1) to ascertain through the eyes of the skilled addressee what is disclosed, explicitly and impliedly, in the original application;

(2) to do the same in respect of the patent as granted; and

(3) to compare the two disclosures and decide whether any subject-matter related to the invention has been added whether by deletion or addition, this comparison being strict in the sense that subject-matter will be added when such matter is clearly and unambiguously disclosed in the application either explicitly or impliedly".

In this case, the court also stated that it is concerned with "what is disclosed, not what have been described".

The Comptroller has also stated that "the fundamental principle in determining additional subject-matter is to decide whether any document presents the informed reader with information relevant to the invention which the other document does not". (Van de Lely's Application ([1987] RPC 61); which is a similar test to that used in Bonzel. However in Southco v Dzus the Court of Appeal made it clear that while the main claim of the patent granted was worded differently from the application filed, the Court of Appeal held that the new wording did not add "fresh subject-matter", so that the claim was valid, even though the claim allowed was possibly broader than that originally filed (but not granted).

As an example of the problems of amendment and of implicit disclosure in Protoned's Application ([1983] FSR 110) an amendment to change "mechanical compression spring" to "mechanical spring" was refused on the basis that the deletion of the word "compression" widened the scope of the claim.

Finally on amendment, if an omnibus claim has been allowed (see above) deletion of descriptive matter must, necessarily, widen the claim (Shoketsu's Patent No. 3 (Sris 0/60/91 (76.09)).

The situation in Germany and Holland

It is at this point that I find myself treading on dangerous ground. However from brief discussions that I have had with German and Dutch lawyers it does appear that, at least in infringement proceedings, the courts in both countries will take a pragmatic view in exactly the same was as Mr Justice Jacob did in Raychem (above). The court will do its best to work out what the patent and the claims mean; and provided it can come to a clear conclusion will then enforce the resulting claims.

As I have indicated above, that seems to me a very sensible approach and much more satisfactory to all concerned than a formalistic, legalistic view of patents and patent claims and patent infringement.

Note: There is a detailed commentary from the National Groups of the AIPPI on "Breadth of Claim, Support by Disclosure and Scope of Protection of Patents" in the Yearbook for Question 142 for the AIPPI Congress in Rio de Janeiro in 1998 (AIPPI Yearbook 1998/IV).